I am designing and building a custom game controller for a school project. However, I can't seem to find much information about the components inside a controller that I would need to build one. I need to build it from scratch, which means that I cannot use parts from disassembled controllers. Can anyone direct me to a resource or let me know what components I would need to make a USB or wireless game controller? Thanks in advance.

I am designing and building a custom game controller for a school project. However, I can't seem to find much information about the components inside a controller that I would need to build one. I need to build it from scratch, which means that I cannot use parts from disassembled controllers. Can anyone direct me to a resource or let me know what components I would need to make a USB or wireless game controller? Thanks in advance.

Sounds like a cool project. I would use a microcontroller that can interface to USB and simulate a HID device. This article should help.
http://www.lvr.com/hidpage.htm